void expressionLL(char* infix, LinkedList *inExpLL) {
  //init variables
  LinkedList *s = malloc(sizeof(LinkedList));
  char tempInt[99]; // to store the string of numbers
  int index = 0;

  while (*infix != '\0') {
    ListNode *temp = malloc(sizeof(ListNode));

    //handles insertion of ListNode into the linked list
    if (inExpLL->head == NULL) inExpLL->head = temp;
    else {
      ListNode *currNode = inExpLL->head;
      while (currNode->next != NULL) currNode = currNode->next;
      currNode->next = temp;
    }

    //checks where the number ends
    while (*infix>=48) {
      tempInt[index] = *infix;
      infix++;
      index++;
    }
    tempInt[index] = '\0';

    //checks if tempInt is populated with numbers. If not, then insert a node that is an operator
    temp->item = (tempInt[0] == '\0') ? *infix : atoi(tempInt);
    temp->type = (tempInt[0] == '\0') ? OPT : OPERAND;

    //if temp's type is OPERAND, insert the current char from infix bc it will be an operator
    if (*infix != '\0' && temp->type != OPT) {
      ListNode *tempOpt = malloc(sizeof(ListNode));
      tempOpt->item = *infix;
      tempOpt->type = OPT;
      temp->next = tempOpt;
    }
    infix++;

    //resets vars for next loop
    tempInt[0] = '\0';
    index = 0;
  }
}